Paint & Coatings Industry - May 2008 - (Page 62)

The Development of New SMA Esters as Pigment Dispersants for Waterborne Coatings and Inks Initial and Aged Dispersion Viscosity Results Initial and aged viscosities for the phthalo blue dispersions are as shown in Figures 3 and 4, respectively. Clearly, the NTX 7639, NTX 7634 and NTX 7643 gave the lowest viscosity, least pseudoplastic results overall. The FIGURE 6 | Aged viscosities (72 hrs) of lithol rubine dispersions versus rpm (shear rate). 18000 16000 14000 Viscosity, cps 12000 10000 8000 6000 4000 2000 0 0 10 02 30 40 50 60 70 Brookfield RPM NTX 7633 NTX 7636 NTX 7643 SMA Ester B SMA Ester A flatter the viscosity curve is, the lower the degree of pseudoplastic, or “shear thinning” character. This is considered advantageous from a handling and use standpoint. In considering the aged dispersions, only the NTX 7643 demonstrated minimal viscosity increase. Initial and aged viscosities for the lithol rubine dispersions are as shown in Figures 5 and 6, respectively. For lithol rubine, the best products for providing lower viscosity and pseudoplasticity are the two controls (SMA Ester B and SMA Ester A) plus NTX 7636 and initially, NTX 7643. Upon aging for 72 hours, the NTX 7634 and NTX 7637 dispersions had gelled too much to be measurable; the two controls and NTX 7643 had doubled in viscosity. However, the dispersion containing NTX 7636 had less viscosity gains. Viscosities for the diarylide yellow dispersions are as shown in Figure 7. Viscosities of the yellow dispersions showed marked differences; the NTX 7636 and NTX 7638 dispersions were similar in viscosity; the NTX 7643 provided much lower viscosities – but the NTX 7639 demonstrated substantially lower viscosities and low pseudoplastic character versus the others. Ink Letdown Procedure and Testing GEO Specialty Chemicals is proud to announce a new line of polymeric polyols to complement our existing family of products: • DMPA® High Acid Polymeric Polyol • DMPA® Hydrocarbon Polymeric Polyol • DMPA® Epoxy Based Polymeric Polyol These new polymeric polyols are specifically designed to help solve today’s environmental challenges while improving the properties needed for today’s high performance resin systems. Contact us for information on how these products can help you achieve the resin properties you are looking for. Clean and Solvent-Free PUD’s: use new DMPA® Polymeric Polyols ® Flexographic inks were then prepared from the dispersions by combining 17.5 g of dispersion with 32.5 g of masstone vehicle. This yields inks with 12.95% pigment loading (lithol rubine and diarylide yellow) and 13.56% pigment loading (phthalo blue). The composition of the masstone vehicle is: ECO 2177 68.42%; Joncryl 63 - 26.32%; and water - 5.26%. Using a Pamarco hand proofer fitted with a 550 line ceramic laser engraved anilox with 2.8 bcm capacity, the inks were printed down side by side on Leneta 3NT-3, 7-mil polyester film and foil (Leneta Alu-Card) and compared for color density, gloss, and transparency. Initially, Brookfield viscosities of the inks and dispersions were measured, and this was repeated at 72 hours. The dispersions containing NTX 7636, NTX 7638 and NTX 7643 had a high degree of air entrainment, which might explain the excessive pseudoplastic character. However, the effects of air would be mitigated at the 60 rpm measurement and, even here, these formulas are much more viscous than the one containing NTX 7639. The finished ink compositions would be as shown in Table 9. 340 Mathers Road Ambler, PA USA 19002-3420 215.773.9280 888.519.3883 (U.S. ONLY) fax: 215.773.9310 trimet@geosc.com www.geosc.com ©Copyright 2007. GEO Specialty Chemicals, Inc. All rights reserved. Ink Viscosities The ink preparation for the phthalo blue samples was straightforward except for the formulas containing SMA Ester B. In this case, the ink demonstrated some shocking upon preparation; hence, ink appearance and viscosity will be suspect. NTX 7638 gave the lowest viscosities and least amount of pseudoplastic behavior, as shown in Figure 8. The aged viscosities are shown in Figure 9. 9/6/07 4:08:18 PM Visit ads.pcimag.com PCI12074Geo.indd 1 62 MAY 2008 | W W W . P C I M A G . C O M http://www.geosc.com http://www.geosc.com http://ads.pcimag.com http://WWW.PCIMAG.COM

Table of Contents Feed for the Digital Edition of Paint & Coatings Industry - May 2008

Paint & Coatings Industry - May 2008 Contents Viewpoint Industry News Calendar of Events Company News Mergers and Acquisitions Names in the News Charlotte Dining Guide Exhibits-in-Print Waterborne Alkyds Break Through the Performance Barrier New Matting Agents for Waterborne Coatings and Varnishes Silicon-Based Technology for the Coatings Industry High-Performance Microgrinding The Development of New SMA Esters as Pigment Dispersants for Waterborne Coatings and Inks The Right Choice New Coating Technology Expands Color Choices for Vinyl Building Products BioPreferred Federal Biobased Products-Preferred Procurement Program European Union's REACH Regulation Sustainability - The New Nano Improved Dirt Pickup Resistance Critical to Future Coating Innovation NanoNews Protective Coatings NDT - Energy-Saving Paint Static Electricity - The Hidden Danger in Hazardous Areas Wacker Chemie - A Profile of Success Materials Watch Products and Literature Classifieds Advertiser Index

Paint & Coatings Industry - May 2008

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